Mars HiRISE Image

Think you're seeing trees on the Martian surface? Guess again - it's an optical illusion. The "trees" are actually dark streaks on the sand caused by evaporating gases. This image is one of thousands in the HiRISE collection.

When someone says the word “Mars,” what image comes to your mind? Most likely, you picture a dusty, cratered, rust-colored wasteland. But thanks to the High Resolution Imaging Science Experiment (HiRISE), you can see our planetary neighbor like never before. The HiRISE camera, part of the Mars Reconnaissance Orbiter, is operated by NASA and the University of Arizona and is currently the most powerful camera on any NASA spacecraft. The beautiful images it has sent back to Earth highlight the fact that while parts of Mars may seem familiar to us, other features of the Red Planet are bizarre and mysterious.

Unlike Mars rovers, which are designed to investigate only a tiny portion of Mars’s land area, the HiRISE camera orbits the entire planet and can be directed to take images of any interesting area. It has taken thousands of detailed images, all of them available to view online. Now, with the release of the HiWish public suggestion tool, you can help determine future target areas for the camera. After registering for the program, you can browse large-scale areas of the Martian surface and send in your suggestion for where HiRISE should take its next close-up image. The site also allows you to track your suggestions and receive notifications when your images are taken.

If you’re interested in finding out more about the Red Planet, plan to attend our Science 360 show “Mission to Mars,” which returns to the MPSC schedule on February 6, 2010.

Casey Rawson is the Science Content Developer for Science 360.

Massive Terrestrial Impact

A huge asteroid like the one in this image (an artistic rendering from NASA) would likely wipe out all life on Earth. But should we be worrying about this happening in 2012?

As if Mayan “doomsday prophecies,” Sun-damaging planetary alignments, and fatal alignments with the galactic center were not enough, 2012 apocalypse proponents are also stating that on December 21, 2012, Earth will be hit by a huge asteroid that will cause mass extinction and global chaos.

As with the other 2012-doomsday scenarios, the asteroid strike claim has a good deal of scientific evidence against it. Of course, asteroids have hit our planet before – scientists believe a huge one (several miles wide) was probably responsible for the extinction of the dinosaurs – and it is virtually guaranteed that Earth will be hit again at some point in the future. But precisely because of that high probability, scientists around the globe are searching the skies for what they call “Near-Earth Objects” (NEOs) that may one day strike Earth.

NASA, in conjunction with several other astronomical organizations around the globe, has been cataloging NEOs since 1998. These organizations search the sky for asteroids and comets that are in Earth’s celestial neighborhood. When one is found, advanced computer programs model the object’s future path, taking into account the object’s size and speed as well as the influences of gravity from the Sun, Earth, and other planets and moons in our solar system. As the object comes closer, we can gather more information about it and further refine this model.

But why are scientists spending so much time searching for NEOs – it’s not like we could stop them from hitting Earth, right? It may sound like something out of a big-budget blockbuster, but astronomers actually do think that we would have a chance of deflecting a comet or asteroid headed for Earth – if we discovered it well enough in advance. Proposed methods for NEO deflection include solar sails, “gravity tractors,” and rockets – but NOT nuclear weapons as seen in Hollywood, which would only break the object apart and send deadly mini-asteroids our way. Russia has recently announced preliminary plans to deflect the asteroid Apophis (which technically has a chance of hitting us in 2036, albeit a very small chance).

So, could an asteroid strike the Earth on December 21, 2012? Sure – but a strike is no more likely on this particular date than on any other. Scientists in the NEO discovery program have not found any large object that is likely to even pass close to Earth on this date, or on any other in the near future. Even if they did, it is likely that we could deflect such an object before it intercepts Earth’s orbit.

To find out more about the 2012 claims, stay tuned to the MPSC blog and plan to attend our Science 360 show “The Truth Behind 2012” when it opens in early February.

Casey Rawson is the Science Content Developer for Science 360. She prefers "Deep Impact" over "Armageddon," if only for the escaping-a-tidal-wave-on-a-moped scene.

Galactic Center

In the heart of the Milky Way lies a supermassive black hole. This infrared image of the center of our galaxy was taken by NASA's Spitzer Space Telescope.

So far in our 2012 blog series, we’ve dealt with the Mayan calendar and claims of a planetary alignment. Another claim making the rounds says that on December 21, 2012, Earth, our Sun, and the galactic center will align, and something about this alignment will cause Earth to be annihilated.

This claim is trickier than most, because it turns out that we will experience a rough alignment of these three celestial objects on 12/21/2012. But don’t start investing in survival supplies just yet: it turns out that Earth, our Sun, and the black hole at the center of our galaxy align like this twice each year – and we’re still here!

We all know that Earth orbits the Sun once each year. What you may not know is that our Sun is also orbiting the center of the Milky Way galaxy. One complete solar orbit takes about 225 million years! As these two orbits are occurring, Earth, the Sun, and the galactic center experience an approximate alignment twice each year. Even this alignment is not perfect, since the Earth and the Sun’s orbits are tilted relative to one another.

2012 doomsayers make a big deal out of the fact that this alignment is occurring on the winter solstice. But the extremely long orbital period of the Sun around the galactic center means that this alignment has occurred on the solstices for years, and will continue to for quite a few more. The bottom line? There is no scientific reason to think that the approximate alignment of Earth, our Sun, and the galactic center will be any different on 12/21/2012 than it was on 12/21/2009.

To find out more about the 2012 claims, stay tuned to the MPSC blog and plan to attend our Science 360 show “The Truth Behind 2012” when it opens in early February 2010.

Casey Rawson is the Science Content Developer for Science 360, and she wonders how a 50-pound drum of coffee would save anyone if a black hole really DID suck in the Earth.

In a celestial tug-of-war between our Sun and the planets, there is one clear winner.

Today is the winter solstice, and those of you paying attention to pop culture might also note that today is exactly three years from December 21, 2012 – the day that Earth will end (if you believe everything you read on the internet). If you saw our first blog post on the 2012 apocalypse claims, you know that modern Mayans are scoffing at the idea that one of their ancient calendars predicts the end of the world. But that hasn’t stopped people from suggesting all kinds of end-of-the-world scenarios for 12/21/2012. One of the most popular is the planetary alignment claim – which says that the planets will align, and the resulting gravitational forces will damage our Sun.

There are two questions here: one, will the planets align on this date? And two, would an alignment damage our Sun, producing fatal effects here on Earth?

The first question is easy to answer. Since planets have such predictable orbits, we can use simple computer programs to track planetary positions for any date – past, present, or future. Try it for yourself at this site – do you see any alignment on December 21, 2012?

The answer to the 12/21/12 alignment question is a simple NO – the planets will not be aligned on that date. But if they were aligned, what would happen?

This question has a simple answer as well, and the answer is: NOTHING. Our Sun is gigantic compared to any of the solar system’s planets. In fact, the Sun makes up 99.8% of the solar system’s total mass. Gravity depends on mass, so the result of any celestial tug-of-war between the Sun and its eight planets is a foregone conclusion: the Sun is going to win, every time.

To find out more about the 2012 claims, stay tuned to the MPSC blog and plan to attend our Science 360 show “The Truth behind 2012” when it opens in early February 2010.

Casey Rawson is the Science Content Developer for Science 360, and she has no plans to start stockpiling toilet paper in preparation for December 2012.

Mayan Calendar

The ancient Mayas viewed time as cyclical, as evidenced by their round calendars. Picture from Wikimedia Commons.

If you’ve been paying attention to pop culture over the past few weeks, you’ve probably heard some rumors about 2012 – specifically, about December 21, 2012. The 2012 buzz includes everything from a giant rogue planet hitting Earth to a fatal alignment with the galactic center. MPSC will be addressing the 2012 apocalypse claims in an upcoming Science 360 program, debuting in early February 2010. Meanwhile, we’ll be blogging about the claims, so check back often for new installments.

Before going into any details about what 2012 proponents claim will happen, we should first answer the question, “Why December 21, 2012?” The answer has to do with an ancient Mayan calendar.

The ancient Mayas used at least three different calendar systems, all of which operated simultaneously. There was a 260-day calendar (most likely based on the passage of Venus through the night sky), a 365-day civil calendar, and the “long count” calendar, which was used to record historical events. It is this last calendar that is being offered as “proof” of a December 2012 apocalypse.

The long count calendar marked the passage of time through lengthy cycles which cover about 5125 years each. The Mayas set the beginning date of the current cycle as August 11, 3114 B.C. (when they believe the world was created). That puts the end of this long count cycle on December 20, 2012. So what will happen on December 21? Will there even be a December 21?

2012 apocalypse promoters would like to you believe that the answer is no. But the Mayas themselves disagree. There are references in Mayan documents to dates both before this cycle began and after this cycle ends. There are also Mayas still living today, mostly in Guatemala, and they are not preparing for an apocalypse! If anything, the end of such a long cycle of time would probably have been a cause for celebration among the ancient Mayas.

So what will happen to the Mayan long count calendar on December 21, 2012? It will simply roll over to a new cycle, just as our desk calendars have to be replaced in January of each year.

To find out more about the 2012 claims, stay tuned to the MPSC blog and plan to attend our upcoming Science 360 show “The Truth Behind 2012” when it opens in early February 2010.

Casey Rawson is the Science Content Developer for Science 360.

Now you can watch the latest Science 360 from the comfort of your own computer screen (although it’s much more fun to come in to see it and check out a Planetarium or laser show while you’re at it). But right now you’re probably sitting on your couch and wondering, “Why do plants have flowers? How do flowers develop? What secrets are hidden in their genes, and how could those secrets affect our lives?” I know you are – don’t lie to me. Watch the vid below and find out the answers. When you’re done, check out some of our other videos on our youtube and vimeo channels.

Jay Heinz is Morehead's Digital Production Manager. He is ready for lunch. No, seriously.

Agression

Could estrogen - the female sex hormone - cause aggression and territoriality in males?

What makes a male behave like a male? Many answers may come to mind – societal expectations, culture and environment, and hormones, to name a few. Hardly anyone would guess that estrogen – the female sex hormone – plays a role in male behavior. Yet this is precisely what a team of researchers at the University of California, San Francisco have discovered: estrogen, rather than testosterone, plays a vital role in “masculinizing” the developing brain shortly after birth. Their research appears in the newest issue of Cell.

Shortly after birth, male gonads release a surge of testosterone into the bloodstream. The UCSF research team discovered that the male brain contains a number of neurons equipped with an enzyme called aromatase, which converts the testosterone into estrogen. Once exposed to estrogen, these neurons establish a particular circuitry that is unique to the male brain and is thought to account for stereotypically male behaviors such as aggression and territoriality.

This theory is strengthened by the fact that female mice who were exposed to estrogen shortly after birth become “tomboys,” exhibiting the same aggressiveness and territory-marking behavior as normal male mice. You might reasonably wonder, if estrogen is the female hormone, why don’t all girls end up acting like boys? It turns out that ovaries typically do not secrete any hormone this early in life, which allows the brain to establish female brain circuitry.

Brain development is an extraordinarily complex subject with many unanswered questions. If you would like to learn more about this topic, come to Morehead Planetarium and Science Center to see the Science 360 presentation “The Developing Brain.”

Casey Rawson is the Science Content Developer for Science 360.

youtube-logoMorehead now has YouTube and Vimeo channels. Check them out here:

http://www.youtube.com/user/moreheadplanetarium

http://vimeo.com/channels/morehead

Right now we’ve got the trailer for our first planetarium show, Earth, Moon and Sun, as well as videos from our Science 360 series that talk about current science topics from stem cells to genetic engineering. Just hit the subscribe button at the top of each page and you’ll be alerted when we put new video content up on the site. Keep an eye out for a couple new Science 360s in the next few months as well as a sneak peak at our next planetarium show.

Jay Heinz is Morehead's Digital Production Manager.

Light Pollution

Light pollution can drastically affect the number of stars visible in the night sky. Click on the picture to enlarge. Picture from http://stellarium.org.

Step outside the average suburban home at night, and you’re likely to see the fluorescent glow of streetlights, soft yellow light streaming from the windows of homes, and security floodlighting. One thing you may not be able to see is the night sky. The light sources around us at night can scatter photons upwards into our atmosphere, creating light pollution that blocks our view of the stars – particularly those stars that are smaller, farther away from Earth, or dimmer. For many urban and suburban dwellers, the only Milky Way they’ll ever see comes in a brown candy wrapper.

Astronomers try to monitor levels of light pollution, because it has serious consequences for scientists’ ability to study our universe (Earth-bound telescopes, just like our eyes, are hampered by light pollution). Astronomers can’t be everywhere in the world, though, so to effectively keep tabs on levels of light pollution around the world, they need the help of ordinary citizens.

From October 9th through the 23rd, you can participate in the Great World Wide Star Count along with thousands of other amateur observers around the world. The idea is simple – everyone will observe the same constellation (if you’re in the Northern hemisphere, you will observe Cygnus) and count the number of stars that are visible. Then, observers will post their results online, where they can also view the project’s results. To participate, simply visit the Star Count website and download an activity guide.

If you are interested in learning more about the relationship between light and astronomy, look for the Science 360 show “Bring the Universe to Light,” coming back on the schedule at Morehead Planetarium and Science Center later this fall.

Casey Rawson is the Science Content Developer for Science 360.

It is officially autumn, and here in North Carolina that means fresh tomatoes, cucumbers, grapes, squash, and, of course, pumpkins will be on display at farmers’ markets across the state. All of these fall treats, along with nearly all the other fruits and vegetables we eat, come from flowering plants.

Luckily for those of us who enjoy fresh produce, flowering plants are some of the most evolutionarily successful organisms on Earth – but their success does not come from luck. Instead, flowering plants have developed survival mechanisms that are almost as varied as their beautiful blossoms: from the color, size, and shape of their petals to their scents or pollen size, these plants are carefully designed to maximize their reproductive success through pollination.

Hornet

This rare orchid produces a chemical that mimics a distressed honeybee. Picture from UK Daily Mail.

Scientists in Germany have recently discovered that one flowering plant – a particular type of orchid – is trickier than most when it comes to ensuring its pollination. Scientists noticed that hornets displayed strange behavior around this flower – they would pounce on the center of the blossoms, as if attacking them. The researchers knew that the hornets typically prey on honeybees, and they discovered that the orchid actually produces the same pheromone released by honeybees as a distress call. The hornets pick up the scent and attack the flower expecting a juicy snack; instead, they unwittingly spread the orchid’s pollen!

This orchid is only one example of the diverse and creative world of flowering plants. To learn more about these incredible organisms, you can attend the Science 360 program “Flower Power,” where MPSC educators will share much more about the flowering plants around you.

Casey Rawson is the Science Content Developer for Science 360.

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